MUE Symptoms

Common MUE Symptoms

MUE can present differently depending on location, progression, and type.

Speed is Critical

If your dog or cat is experiencing symptoms, you must act quickly to avoid irreversible neurological damage.

Please view the Diagnosing page to learn more.
MUE is a rapidly progressive disease with different symptoms based upon the location of the inflammation and presence of granuloma clumps in the brain, spinal cord, or eyes.

Most animals are first diagnosed with something else like luxating patellas, uinary tract infections, ear infections, back pain, and more.

While each dog or cat will have their own disease progression unique to them, here are some of the common symptoms:
  • Central vestibular signs such as the following which get progressively worse and more frequent:
    • strange head posturing
    • circling
    • head tilting
    • posturing the head backwards or forwards because that is what feels "normal"
    • balance issues
    • difficulty walking
    • limb tremors, weakness in the limbs,
    • issues with depth perception resulting in issues with going up/down stairs
    • over-exaggerating jumping over thresholds
    • wide stance when standing
    • flickering the eyeball from side-to-side or up and down
  • Progressively worsening behavior abnormalities like withdrawing from in normal activities, disorientation, or apathy.
  • Progressively worsening seizures.
  • Progressively wrosening neck and or back pain.
  • Progressively worsening weakness in some or all limbs (called para or tetraparesis).
  • Progressively worsening tremors.
  • Acute onset of blindess.

You can read about Piper's GME experience here.


Below are the common symptoms based on location of GME:
Fore brain: cerebral cortex and thalamus
  • Seizures
  • Behavioral changes such as loss of training, failure to recognize family members, aggression, or hyper-excitability
  • Altered mental status (withdrawn, apathy, depression, disorientation, or lack of energy, inactivity, lethargy)
  • Abnormal movements or postures (circling, pacing, wandering, head-pressing)
  • Loss of function on one side of the body like vision, facial expression, etc.

Cerebellum
  • Lack of coordination or unsteady movements (called ataxia)
  • Tremors
  • Overestimation or overshooting of movements (called hypermetria). Example: Instead of walking over a door threshold, jumps over it completely
  • Broad-based stance
  • Loss or impairment of the menace response (a reflexive blink response that occurs when a bright light is suddenly directed toward the eye)
  • Neck pain (cervical pain)
  • Abnormal head positioning

Mid-Brain 
  • Muscle weakness or paralysis of one up to all four limbs (called upper motor neuron paresis/paralysis)
  • Inability to return the paw to normal position if flexed so the top of the paw is upside down called (postural reaction deficits all four limbs or contralateral to lesion)
  • Mental depression
  • Ipsilateral oculomotor and trochlear deficits
  • Hyperventilation
  • Neck pain (cervical pain)

Hypothalamus
  • Seizures
  • Normal gain
  • Disorientation
  • Withdrawn, inactive, lethargic
  • Changes in behavior such as aggression or hyper-excitability
  • Abnormal movements/postures - tight circling, pacing, wandering, head-pressing, trembling
  • Abnormal temperature regulation
  • Abnormal appetite
  • Endocrine disturbances

Brain Stem
  • Weakness or partial paralysis affecting one side of the body or limbs on the same side of the body as the inflammation
  • Inability to maintain balance and control posture on the same side of the body as the affected area
  • Cranial nerve abnormalities V-VII, IX-XII resulting in a variety of symptoms such as paralysis of the muscles needed for chewing, facial pain, loss of taste, facial dropping, difficulty losing the eye, drooling or difficulty with facial movements, loss of sensation in the throat, rapid heart rate, trouble swallowing, or weakness or paralysis of the muscles in the head and neck
  • Altered mental status: depression 
  • Irregular respiration
  • Neck pain (cervical pain)


Ocular: 

  • Sudden blindness

Other Diseases That Have Symptoms Similar To MUE

  1. Infectious Meningitis/Encephalitis: Various infectious agents can cause meningitis or encephalitis in dogs, such as bacterial, viral, or fungal infections. These conditions can present with similar symptoms to GME, including fever, neurological deficits, and inflammatory changes in cerebrospinal fluid (CSF). Diagnostic tests like CSF analysis, blood cultures, or polymercase chain reaction (PCR) testing may be required to differentiate between infectious causes and GME.

  2. Parasitic encephalitis: Disease syndrome caused by a protozoan organism called Toxoplasma gondii.

  3. Brain Tumors: Certain types of brain tumors, such as lymphoma or gliomas, can have clinical signs that overlap with GME. Tumors can cause progressive neurological deficits, seizures, and behavioral changes, similar to GME. Advanced imaging techniques like an MRI is often necessary to differentiate between tumor-related conditions and GME.

  4. Intervertebral Disc Disease (IVDD): IVDD is a common spinal disorder in dogs, characterized by the herniation or degeneration of intervertebral discs. Depending on the location of the affected disc, IVDD can mimic GME by causing spinal cord compression and resulting neurological deficits. Diagnostic imaging, such as radiographs or MRI, can help differentiate between IVDD and GME.